The present invention relates generally to drive systems on agricultural implements, and more specifically, to drive assemblies for powering pickup and feed mechanisms from ground engaging wheels.
Many farm implements utilize chain and sprocket drives from ground engaging wheels to power various pickup or feed mechanisms. Many times these drives are a source of trouble since the chain is subject to fouling by dirt, mud, rocks and weeds. The sprockets can build up with dirt and cause the chain to fail to release from the sprocket. Space is often limited around the drive wheel and around the implement frame, making routing of the chain very difficult. Also, access to the chain and sprockets is hindered making adjustments time-consuming and difficult. When needed adjustments are not made, failure of the chain drive is commonplace. In many applications, the position and angle of the drive axle shaft may vary with respect to the rest of the drive making alignment and adjustments in slack continuing problems. Such problems occur frequently, for example, in press wheel grain drills which utilize the press wheels to drive the seed and/or fertilizer metering mechanisms. The chain and drive sprockets of such a grain drill are situated such that dirt and other debris subject the drive to wear and dirt buildup which lead to premature failure. The press wheels are often narrowly spaced and access to the chain and sprockets is limited so that maintenance is often neglected. The press wheel gangs are pivotally connected to the drill frame to accommodate surface variations and obstacles, and therefore the position and angle of the drive axle can vary considerably during field operations.